package com.tistory.aircook;
import java.security.MessageDigest;
import javax.crypto.Cipher;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.SecretKeySpec;
import org.apache.commons.codec.CharEncoding;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.codec.binary.Hex;
public class Crypto {
public static void main(String[] args) {
String str1 = "암호화되지 않은 문자";
System.out.println("plain : " + str1);
String str2 = encryptAES128(str1);
System.out.println("AES128 encrypted : " + str2);
String str3 = decryptAES128(str2);
System.out.println("AES128 decrypted : " + str3);
String str4 = encryptAES256(str1);
System.out.println("AES256 encrypted : " + str4);
String str5 = decryptAES256(str4);
System.out.println("AES256 decrypted : " + str5);
String str6 = encryptSHA256(str1);
System.out.println("SHA256 encrypted : " + str6);
}
// 키
private final static String KEY = "01234567890123456789012345678901";
// 128bit (16자리)
private final static String KEY_128 = KEY.substring(0, 128 / 8);
// 256bit (32자리)
private final static String KEY_256 = KEY.substring(0, 256 / 8);
// AES 128 암호화
public static String encryptAES128(String string) {
try {
byte[] keyData = KEY_128.getBytes(CharEncoding.UTF_8);
// 운용모드 CBC, 패딩은 PKCS5Padding
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// key 와 iv 같게..
// 블록 암호의 운용 모드(Block engine modes of operation)가 CBC/OFB/CFB를 사용할 경우에는
// Initialization Vector(IV), IvParameterSpec를 설정해줘야한다. 아니면 InvalidAlgorithmParameterException 발생
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(keyData, "AES"), new IvParameterSpec(keyData));
// AES 암호화
byte[] encrypted = cipher.doFinal(string.getBytes(CharEncoding.UTF_8));
// base64 인코딩
byte[] base64Encoded = Base64.encodeBase64(encrypted);
// 결과
String result = new String(base64Encoded, CharEncoding.UTF_8);
return result;
}
catch (Exception e) {
return null;
}
}
// AES 128복호화
public static String decryptAES128(String string) {
try {
byte[] keyData = KEY_128.getBytes(CharEncoding.UTF_8);
// 운용모드 CBC, 패딩은 PKCS5Padding
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(keyData, "AES"), new IvParameterSpec(keyData));
// base64 디코딩
byte[] base64Decoded = Base64.decodeBase64(string.getBytes(CharEncoding.UTF_8));
// AES 복화화
byte[] decrypted = cipher.doFinal(base64Decoded);
// 결과
String result = new String(decrypted, CharEncoding.UTF_8);
return result;
}
catch (Exception e) {
return null;
}
}
// AES 256 암호화
public static String encryptAES256(String string) {
try {
byte[] key256Data = KEY_256.getBytes(CharEncoding.UTF_8);
byte[] key128Data = KEY_128.getBytes(CharEncoding.UTF_8);
// 운용모드 CBC, 패딩은 PKCS5Padding
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
// key 와 iv 같게..
// 블록 암호의 운용 모드(Block engine modes of operation)가 CBC/OFB/CFB를 사용할 경우에는
// Initialization Vector(IV), IvParameterSpec를 설정해줘야한다. 아니면 InvalidAlgorithmParameterException 발생
// AES 256은 미국만 되는거라. JDK/JRE 패치를 해야된다.
// http://www.oracle.com/technetwork/java/javase/downloads/index.html 에서
// Java Cryptography Extension (JCE) Unlimited Strength Jurisdiction Policy Files for JDK/JRE 8 이런 링크 찾아서 다운
// $JAVA_HOME\jre\lib\security 아래에 local_policy.jar, US_export_policy.jar 파일 overwrite!
// iv값이 16자리가 아니면..
// java.security.InvalidAlgorithmParameterException: Wrong IV length: must be 16 bytes long 발생
cipher.init(Cipher.ENCRYPT_MODE, new SecretKeySpec(key256Data, "AES"), new IvParameterSpec(key128Data));
// AES 암호화
byte[] encrypted = cipher.doFinal(string.getBytes(CharEncoding.UTF_8));
// base64 인코딩
byte[] base64Encoded = Base64.encodeBase64(encrypted);
// 결과
String result = new String(base64Encoded, CharEncoding.UTF_8);
return result;
}
catch (Exception e) {
return null;
}
}
// AES 256복호화
public static String decryptAES256(String string) {
try {
byte[] key256Data = KEY_256.getBytes(CharEncoding.UTF_8);
byte[] key128Data = KEY_128.getBytes(CharEncoding.UTF_8);
// 운용모드 CBC, 패딩은 PKCS5Padding
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, new SecretKeySpec(key256Data, "AES"), new IvParameterSpec(key128Data));
// base64 디코딩
byte[] base64Decoded = Base64.decodeBase64(string.getBytes(CharEncoding.UTF_8));
// AES 복화화
byte[] decrypted = cipher.doFinal(base64Decoded);
// 결과
String result = new String(decrypted, CharEncoding.UTF_8);
return result;
}
catch (Exception e) {
return null;
}
}
public static String encryptSHA256(String string) {
try {
MessageDigest messageDigest = MessageDigest.getInstance("SHA-256");
byte[] stringBytes = string.getBytes();
int stringBytesLength = stringBytes.length;
byte[] dataBytes = new byte[1024];
for (int i = 0; i < stringBytesLength; i++) {
dataBytes[i] = stringBytes[i];
}
messageDigest.update(dataBytes, 0, stringBytesLength);
byte[] encrypted = messageDigest.digest();
// hex, 16진수
// StringBuffer sb = new StringBuffer();
// for (int i = 0; i < encrypted.length; i++) {
// sb.append(Integer.toString((encrypted[i] & 0xff) + 0x100, 16).substring(1));
// }
// 결과
// String result = sb.toString();
// commons codec lib 사용하면 아래처럼 간단하게..
// String result = Hex.encodeHexString(encrypted);
// base64 인코딩
byte[] base64Encoded = Base64.encodeBase64(encrypted);
// 결과
String result = new String(base64Encoded, CharEncoding.UTF_8);
return result;
}
catch (Exception e) {
return null;
}
}
}
BigGridDemo.java
Excel_Big.zip
